Dry extraction carpet cleaning methods bring liquid chemical cleaning agents into contact with soiled carpet fibers by means of a particulate carpet-cleaning composition. Many tiny porous particles, partially saturated with specific liquid cleaning agents, are applied to the carpet and brushed through it in a specific manner. With this action the moist particles remove the soil from the carpet fibers and the carpet is left dry and clean after vacuum removal of the now-soiled particles.
In the application of particulates for dry extraction carpet cleaning, there are a number of specific problems and concerns. Because of this, spreading has often been accomplished by manual methods, rather than by use of wheeled applicators. There is a need for an improved applicator for use in the dry carpet-cleaning industry.
Certain liquid cleaning agents in carpet-cleaning particulate carpet-cleaning compositions are rather volatile, and if the particulate compositions are left exposed to the atmosphere for an extended period of time the volatile content is greatly reduced or lost. Once dried out, such particulate compositions are of little value in carpet-cleaning operations.
Therefore, it is important to store such particulate carpet-cleaning compositions in closed substantially vapor-tight containers. Such compositions usually come in vapor-tight bags. After removal from their original packaging and loading into an applicator for spreading onto carpets, they must then either be used or else returned to a substantially vapor-tight container. Overnight storage in an applicator between carpet cleaning jobs often will result in unacceptable loss of volatiles.
There is a need for an improved applicator for such particulate compositions which will allow extended (for example, overnight) storage of the composition in the applicator, eliminating the inconvenience of removing it from the applicator into a sealed container.
Another concern with respect to the handling of such particulate carpet-cleaning compositions relates to obtaining proper adjustment of an applicator, that is, to a selected dispensing setting or to a closed condition. Adjustment of such applicators may be difficult at best and controlling the dispensing of such particulate compositions is a specific concern of carpet-cleaning professionals.
Making an applicator substantially vapor-tight and making it easily adjustable tend to be at cross purposes. There is a need for an improved applicator for particulate carpet-cleaning compositions which is both constructed to be substantially vapor-tight when closed and yet may be easily adjusted to various dispensing positions and a closed position.
The characteristics of such particulate carpet-cleaning compositions are of great importance to how well they function. Certain highly effective compositions of this type are made up of porous particles which are of irregular sizes and irregular shapes and significant amounts of liquids. Because of these characteristics such compositions are not free flowing, but often agglomerate to some extent such that dispensing onto carpets by means of an applicator is difficult.
While there have been many different applicators for various particulate compositions, including those having wheels on either side of an apertured dispensing container which dispenses the composition upon rotation about a horizontal axis, it has been found that particulate carpet-cleaning compositions of the type described are not properly dispensed using such prior art devices.
Such carpet-cleaning compositions will flow inconsistently if at all through the typically small apertures in such apertured dispensing containers. Even with larger apertures of the type which are adjustable in size, dispensing is uncontrollable or impossible. Unacceptably erratic dispensing rates occur, particularly when the apertured dispensing container is either full or fairly close to empty. The particulate carpet-cleaning composition often "bridges" even fairly large dispensing apertures if they have sharp corners or irregular shapes.
For carpet cleaners, predictability of dispensing rates is of great importance. Even dispensing allows better cleaning and allows better cost estimates.
While applicators for particulate carpet-cleaning compositions have been developed in the past, such compositions are frequently applied by hand. That is, the operator throws handfuls of the particulate composition onto the carpet before the brushing and subsequent removal. An improved applicator would clearly be of great usefulness.
Some particulate spreaders of the prior art are rather difficult to fill. A variety of filling mechanisms are disclosed in the prior art, including some with end openings, often requiring removal of a wheel or disassembly of the container, and some having lateral doors or alignment apertures. In some cases, a supply of particulate materials is stored in a separate container above the turning mechanism, making the devices much more complex.
In some cases, the filling process itself can tend to cause excessive spilling of the particulate composition.
There is a long-standing need for an improved applicator for spreading particulate carpet-cleaning compositions. More specifically, there is a need for an improved applicator providing reliable control of the dispensing rate for non-free flowing particulate carpet-cleaning compositions which is simplified in structure and operation, which serves both as a containment vehicle and as a substantially air-tight dispenser, and which allows quick and easy filling without losing control of the particulate composition.